Objective:To observe the expression and location of IL-17A in the liver fibrosis and evaluate the clinical significances of IL-17A. Methods:The peripheral blood and liver tissue was collected from the patients with liver fibrosis. The serum IL-17A level was assayed by ELISA,and the expression and location of IL-17A in the liver tissue was detected by immunohistochemistry. Results:Serum IL-17A level was significantly higher in cirrhotic patients than in control. IL-17A was mainly expressed in hepatic stellate cells,infiltrative neutrophil and lymphocyte,and bile ducts epithelium in the liver fibrosis tissue. The IL-17A expression in liver was correlated with Child-Pugh grades. Conclusion:IL-17A is critical in liver fibrosis,and the expression level of IL-17A may indicated the severity of liver fibrosis.